Antenna support structure



Nov. 11, 1969 c, c, MOORE 3AW7Q7U ANTENNA SUPPORT STRUCTURE Filed March 22, 1967 V 2 Sheets-Sheet 1 WVENTOR CLARENCE c. MOORE BY 2 Z Qm-MW l ATTORNEYS.

1969 c. c. MOORE 3,477,676

ANTENNA SUPPORT STRUCTURE Filed March 22, 1967 2 Sheets-Sheet 2 INVENTOR CLARENCE C. MOORE Y fimawwm M ATTORNEYS United States Patent 3,477,676 ANTENNA SUPPORT STRUCTURE Clarence C. Moore, P.O. Box 1000, Elkhart, Ind. 46514 Filed Mar. 22, 1967, Ser. No. 625,102 Int. Cl. A47b 95/06; F16m 13/02 Us. or. 24s 201 2 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION Loop antenna systems, such as described and claimed in myPatent No. 2,537,191, have been supported by a structure including a center support formed by a cast one-piece structure having four legs extending therefrom, and a slotted sleeve adapted to be clamped about a fiberglass or aluminum boom pole. The slotted sleeve of the casting is clamped or bolted together by the insertion of a bolt in a hole crosswise to the slot in order. to spring the casting and secure the center support casting on the boom pole. Respectively connected to the four legs of the cast center support are four poles upon which are mounted the wires of the loop antenna.

This type of a center support structure presents several disadvantages. One disadvantage is that a cast one-piece, four-legged structure is relatively expensive to manufacture, and because of its relatively large size it is difficult to tumble in a foundry cleanup barrel for finishing. A further disadvantage of this single casting is that a relatively large container is needed for shipping. Another disadvantage is that the cast single-piece, center support structure can be used with a boom pole of only one diameter. A still further disadvantage is that Whenever additional elements are desired to be added to the boom pole, they have to he slipped over the end of the boom pole in the desired consecutive order. In fact, the center support structure may even have to be removed before the additional elements can be added.

SUMMARY OF THE INVENTION It is an object of this invention to provide a new and improved center support structure for a loop antenna.

Another object is to provide a relatively inexpensive center support structure for a loop antenna formed by compact parts which can be more easily cast, finished and packed for shipment.

A further object of this invention is to provide a center support structure for a loop antenna which can be clamped around any size center boom.

A still further object of this invention is to provide a center support structure for an antenna which would allow the addition of other elements to the supporting boom Without having to slip them over the end of the boom.

In one embodiment of the invention a center support structure for a loop antenna includes four detachable leg members which can be readily placed around the boom pole of the antenna system in equal angular displacement from each other. Each of the detachable leg members has a base with an arched surface which makes Patented Nov. 11, 1969 contact with the boom and a tapered, tubular or hollow body for reception therein of a pole which, in conjunction with the other poles, supports the antenna wires. The boom can be of various sizes, and with a boom of larger diameter, longer bolts are used and there is a greater surface along the circumference which does not make contact with the arched surfaces of the leg members. With the equal angular displacement of the legs around the circumference of the boom, the legs are bolted together and to each other either directly or by means of a bracket inserted between adjacent legs and bolted to the adjacent legs. Each leg member may be cast as an integral device or may be formed by a taperedhollow portion secured to an arcuate bracket portion. In either case adjacent leg members are bolted to each other. Poles for supporting the antenna wires are secured within each of the legs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an illustration of the general structure of a loop antenna system;

FIG. 2 shows the known construction of the center support structure for a loop antenna;

FIG. 3 shows the center support structure in acordance with one embodiment of the invention;

FIG. 4 is a top view of the embodiment of FIG. 3;

FIG. 5 shows a second embodiment of the invention;

FIG. 6 is an exploded perspective view illustrating the embodiment shown in FIG. 5;

FIG. 7 is a cross-section view of the leg of FIG. 6 along the line 77; and

FIG. 8 is a cross-section view of the leg of FIG. 6 along the line 8-8.

DETAILED DESCRIPTION Referring now to the drawings, FIG. 1 illustrates a loop antenna system utilizing the support of the invention. Mounted on top of a tower 10 is. a rotary coupler 12 to which a boom or boom pole 14 is attached by means of a boom plate 16. The boom 14 is thus held in place and is rotatable from a ground position through the rotary coupler 12. A center support structure 18 is mounted on each end of boom 14. The center support structure has four separate legs or leg members 20 to which are attached poles, which may be fiberglass poles 22, to which are fastened the antenna wires 24 for the loop antennas. The fiberglass poles 22 can, support several dilferent antenna wires 24 having different loop dimensions and thereby provide multiband radio operation.

FIG. 2 shows the construction of the known antenna center support structure that is presently being used. It should be noted that this is a one-piece cast structure having four legs or leg members 25 which are uniformly displaced around a slotted center sleeve 26. Bolts 27 are provided in holes which run crosswise of the flanges 29 which form the slot. The unitary or one-piece support structure is slid over a ooom (14 in FIG. 1) and secured thereby by use of the bolt 27 and nut 28. It will be apparent that this center support structure is usable only with a boom of a diameter slightly smaller than the inside diameter of the sleeve 26.

FIGS. 3 and 4 show the center support structure of the invention in more detail. As best shown in FIG. 4, each of the leg members 20 has an arcuate base 32 with a flanged section 34 at each end thereof and a tubular portion 36 extending therefrom. A reinforcing web 35 extends from each flanged section and along the part of the tubular portion 36 adjacent the base, thereby imparting a tapered shape to the leg member 20. The antenna supporting pole 22, which may be of fiberglass, is held in the tubular portion 36 and is secured therein by a 3 bolt 40. Each flanged section 34 has two holes 39 therein to receive bolts for securing the leg members together.

The individual leg members 20 are positioned around the boom pole and secured together. by inserting the bolts 31 through the corresponding holes 39 in the abutting flanged sections 34 of adjacent leg members 20 and securing the bolts therein by use of the nuts 30. The arcuate base portions thus form a sleeve about the boom, pole. It should be noted that this structure is not limited to use with a boom pole of one size. For use with larger diameter boom poles, longer bolts would be used, and the flanged portions therefore would not abut when the center support structure is assembled around the boom pole but would be separated by some fixed distance dependent upon the'diameter of the boom pole being used.

:FIGS. and 6 show a second embodiment of the invention wherein the parts are formed of sheet metal. The leg members 20 are formed by tapered, hollow portions 38 and connecting brackets 42. Each of the brackets 42 has an arcuate base 43 and a flanged section 44 at each end of the arcuate base. There are two parallel holes 45 (FIG. 6) at a predetermined distance apart in each of the flanged sections which mate with corresponding holes in the hollow leg portions 38 for reception of bolts 51. There are also two parallel holes 47 at the ends of the arcuate base 43 of each of brackets 42 for receiving screws which extend into the boom pole 14. The hollow leg portions 38 each receive one of the fiberglass poles 22 which support the antenna lines.

The center support structure is attached to the boom pole by placing the brackets 42 between adjacent hollow leg portions 38, and bolting the same together as shown in FIG. 5. This arrangement, when assembled around a boom pole 14, provides a strong center support structure for the fiberglass poles. The screws 46 inserted through the holes' 47 in the arcuate or arched portions of the bracket and into the boom pole 14 prevent rotation of the center support structure around the boom pole. It should be further noted that this embodiment can also be used with larger diameter boom poles by utilizing larger brackets having arcuate surfaces which encompass a greater arc.

FIGS. 6, 7 and 8 show the taper on the hollow leg portion 38 for receiving the fiberglass pole. Holes 49 are provided for bolting the fiberglass pole 22 (FIG. 1) to the leg portion 38.

The new and improved center support structure for a loop antenna can be clamped around a center boom having a circumference of different sizes and does not have to be slipped over the end of the boom. Because of its detachable multiple leg structure, it can be molded in a small cast and the same cast can be used for all four legs. The smaller parts can be more easily tumbled in a foundry cleanup barrel for finishing and thereafter can be more easily shipped in a relatively small container.

What is claimed is:

1. A support structure for a loop antenna having antenna wires, antenna poles for supporting the antenna wires, and a substantially horizontal boom pole, such support structure including in combination, four separable leg devices each having a first portion for receiving an antenna pole and a second connecting portion, said first portion of each device having a'tapered body for receiving an antenna pole with a hole therethrough, each of. said second connecting portions having an arcuate boompole engaging surface with a flanged section at each end thereof, each of said flanged sectionsof said connecting portions having a hole therethrough, fasteni ing means cooperating with said flanged sections for connecting adjacent ones of said leg devices to form a hol low sleeve, said fastening means extendingthrough said holes in said bodiesand in said sections to connect said first receiving portions and said second connecting portion in alternate relation to form said hollow sleeve, said sleeve being adapted to receive the boom pole with said arcuate surfaces of said connecting portions engaging the boom pole, said first and second portions of said leg devices being in fixed positions with respect to eachother with said first portions positioned to hold the antenna poles perpendicular to the boom pole, and means forre' spectively securing the antenna poles to said first "portions of said leg devices.

2. A support structure for a loop antenna having an-T tenna wires, antenna poles for supportingthe antenna wires, and a substantially horizontal boom pole, such' support structure including in combination, four separable leg devices of the same configuration and each having a first portion for receiving an antenna pole and a second connecting portion, said first portion of each device having an elongated tubular body adaptedto receive an antenna pole, each of said second connecting portions. having an arcuate boom pole engaging surface with a flanged section at each end thereof, each of said flanged sections of said connecting portions having a hole therethrough, fastening means extending through said holes in said flanged sections for connecting adjacent ones of said leg devices to form .a hollow sleeve, said sleeve being adapted to receive the boom pole with said arcuate surfaces of said connecting portions engaging the boom pole, said fastening means being adapted to connect said flanged sections of said second connecting portions with References Cited UNITED STATES PATENTS 927,745 7/1909 1,575,614 3/1926 Blaw 248230 X 1,843,454 2/1932 Manson 248221 2,908,469 10/1959 Mack et a1. 248- 230 OTHER REFERENCES QST, Ernest H. Adolph, An Interlaced Quad Array for and 144 MC., February 1963, pp. 11 to 14,

ROY D. FRAZIER, Primary Examiner J. F. FOSS, Assistant Examiner US. Cl. X.R.

Murphy 248-230- 

